Process and apparatus for discharging vaporizable liquids



Feb. 14, 1950 R BAKER ET AL 2,497,754

PROCESS AND APPARATUS FOR DISCHARGING VAPORIZABLE LIQUIDS Filed Aug. 24, 1959 2 Sheets-Shet 1 Fig. 1

awumflm 120mm I'fbAKER JAMES C. FLEMING ;Feb.14,1950 R ETA 2,497,754

R. BAKE L PROCESS AND APPARATUS FOR DISCHARGING VAPORIZABLE LIQUIDS Filed Aug. 24, 1959 2 Sheets-Sheet 2 a 95 3) E o\ g ,\7 [I I H in m I i I I woman Patented Feb. 14, 1950 PROCESS AND APPARATUS FOR DISCHARG- IN-G 'VAPORIZABLE LIQUIDS RobinBaker, Lockney, and James .G. Fleming Lubbock, Tex.

Application August 24, 19.39, Serial No. 291,796

7 Claims.

The present invention relates to an improved method and apparatus for use in the handling of gaseouszfuels but moreparticularly has for its object-to provide an improved method and ap-. paratus for handling liquefied fuel.

The use of liquefiedfuel'for domestic and commercial purposes has become quite common in various sections of the United States. At temperatures below 32 'F. liquefied fuelis in liquid state and if kept under pressure may be maintained in, a liquid statev at higher temperature. Tanks in which liquefied fuel is stored are usually operated under pressure obtained through higher. temperatures or other methods.

In the various forms of tanks heretofore used, the upper portion of the tank fOI'IIlSa the main evaporating chamber, whereby the lighter gases evaporate. first and the evaporation continues until the liquid residue left, in the bottom of the tank is of such a heavy nature that evaporation all timesand whereby no residue accumulates in the bottom of thefuel tank.

This object is achieved by removing the liquefied fuel from apoint near the bottom of the tank in a manner similar to that disclosed in our copending application, SerialNo. 213,946, filed June 16, 1938, now Patent 2,339,134, granted January 11, 1944. In the invention comprising the present application, however, the liquid drawn ofi from thebottom of the tank is vaporized inystages and the sensible heat of the liquid in the tank made use of to more fully vaporize the. fuelgas before passing it to the desired point of use. This result is achieved by passing the liquid drawn off from the bottom of the tank under reduced pressure through apipe system immersed in the liquee 'fied fuel, and making use ofthe sensible heat "thereof? to fully vaporize the liquefied mel thus drawn off. Thethus ,fullyvaporized liquefied fuel .is then passed through a conventional control valve; and. pressure regulator to, the, point of use, suchas an ordinarygasstove.

Another. object of theinvention is to set upan agitation. and circulation. of the, liquefied fuel. in

bvreasouof. the unequal, temperatures.

2 caused. by theexpansion and evaporation. of the fuel drawn, 01f...

Weghave illustratedin the accompanying drawings a preferred embodiment of this invention together with, a modification thereof, but it is to be understood. that the design may be varied and changes made in the details of construction withthe scope of the invention as claimed, without departing from the spirit thereof.

In the accompanying drawings:

Fig. 1 is a vertical longitudinal section, parts being shown in elevation, of a. fuel tank and. fittings, embodying the invention;

Fig. 2 is a cross-section taken on the line 2-2 of Fig. 1;

Fig. 3 is a vertical longitudinal section, parts being shown in elevation, of a modified form of the invention Fig. 4; is a cross-sectional view taken on the line 4 -14 of Fig. 3;; and

Fig. 5 is a cross-sectional view taken on the line .5--5v of, Fig. 3..

Referring specifically to the form of the invention shown in Figs. 1 .and 2 of the drawings, the numeral 1 indicates a fuel tank adapted to receive, and enclose the liquefied fuel under normal working pressure.

Extending into the tank I and to a point close to the bottomthereof is a draw-off pipe 2. The liquefied fuel drawn from the bottom of the tank I is, passed up through the pipe 2 through a pressure regulator 3 which passes the, liquefied fuel under a reduced pressure of 3-5 pounds per square inch to a pipe 4.

The pipe 4 passes the fuel back into the tank and throughacoil 5. which is mounted on rods 6 secured in the tank I. The coil 5 is submerged beneath the level of the liquefied fuel in the tank I.

The liquefied fuel after, passing through coil 5 is passed out of the tank I through a pipe I and to the low pressure regulator 8 thence through a pipe 9 to the point of consumption.

The gas line; 9 is provided with, a manually controlled valve L6 as, well as the pressure regulator. 8 which holds the; back pressure in the pipe lines I and 4. and. coil. 5,. A. pressure gauge I,8 may be Provided andv connected, with the pipe 1 to indicate the pressure of the gas passing therethrough, andlikewise. the pressure in the, pipe line 1, and and, coil 5,.

As. the liquid passes. throu h th pressure resulator 3.120. the pipe. line .4 under a reduced. pres sure. expansion of. the. liquefied fuel takes place resulting; in, vaporiza ion. and a reduction in. tern:

perature. In passing through the coil 5 the partially vaporized fuel will be further vaporized due to the warming action caused by the sensible heat of the liquid fuel in the tank I. The warmed and fully vaporized fuel is then passed through the regulator 8 and pipe line 9 for consumption. Due to the thermal instability caused by the difference in temperatures of the liquid fuel in the tank and the gaseous vapor in the coil 5, an agitation is set up which will keep the liquids of diiferent specific gravities mixed in a uniform manner. However, drawing the liquefied fuel from the bottom of the tank will ensure the elimination of any residues being left therein.

Commercial butane gas contains approximately 7 butane which has a boiling point of 32 F.

and weighs approximately 4.8 pounds per gallon.

It contains approximately 3260 B. t. u. per cubic foot, and at 60 F. the gas enclosed within a tank will exert a pressure of approximately twenty pounds per square inch. Commercial butane also contains isobutane and propane in about equal proportions. Isobutane has a slightly greater specific gravity, weighing approximately four pounds and fourteen ounces per gallon, and at 60 F. will exert a pressure of approximately thirty-five pounds per square inch in a tank. The boiling point of isobutane is approximately 12 F. and it contains approximately 3000 B. t. u. per cubic foot. Propane weighs approximately four lpounds four ounces per gallon and at 60 F. exerts a pressure of approximately ninety pounds per square inch in a tank. The boiling point is approximately 44 F. and it has approximately 2550 B. t. u. per cubic foot. are also traces of heavier fuels in the liquified gas; consequently when the fuel remains in. an unagitated static condition, these liquids of varying specific gravities tend to stratify, which harppens when evaporation methods used heretofore are employed.

By this invention, the liquids are kept in an agitated state which results in drawing off a uniform mixture from the tank.

The liquefied fuel tank is usually buried in the ground, and to provide access thereto and to the fittings thereof, a housing [9 extends upwardly from the tank to the surface of the ground, enclosing the fittings. The hood or housing I9 has a removable cover hinged thereto.

The outlet tube 1 and pressure regulators 3 and 8 are enclosed within the housing l9. Also enclosed within the housing and connected with the top of the tank I are a filling pipe 22 and a vent pipe 23, both (provided with conventional valves 24 at the upper ends thereof. A gauge tube 25 extends through the top of the tank to a point near the bottom thereof and has its upper end enclosed in a housing 26.

Valves l0 and H, for manual control of the fuel coming from the tank and passing back therein, may be mounted on either side of the pressure regulator valve 3.

The modification of the invention which is somewhat shown in Figs. 3, 4 and 5 is similar in operation and structure to the form described above. The reference numerals used in designating like parts will have attached thereto the letter a.

In this modified form an auxiliary tank 12 is used apart from the main fuel tank la. The fuel coming from the regulator valve 3a under reduced pressure is conveyed through the pipe 4a to the auxiliary tank I 2 and the coil 5a mounted therein on the rods to. The tank [2 is kept filled with There liquefied fuel and the sensible heat of this liquid is made use of for the further vaporization of the fuel.

A housing I3 extends above the auxiliary tank l2 and encloses the fill pipe l4, pipe to, pressure regulator 80, and pipe line 9a. A cover l5 may be removably mounted thereon.

While the system has been described in connection with commercial butane gas, it is to be understood that any liquefied fuel suitable for the purpose may be utilized in the practice of the invention.

We claim:

1. A fuel supply apparatus comprising a tank adapted to contain a liquid under pressure, means to withdraw liquid from a point adjacent the bottom of said tank, means to reduce the pressure of said withdrawn liquid to cause vaporization thereof, a coil immersed in the liquid in said tank, means to pass the vaporized liquid to said coil and means to direct the vapors from said coil.

2. In combination in a liquefied gas storage and dispensing system, a tank, and a take-off con-' nection comprising conduit forming means in communication with the interior of said tank, a pressure reducing regulator connected in communication with said conduit, a vaporizing coil within said tank in a position to be immersed in liquid therein, a connection from said regulator to said vaporizing coil and a second connection from said vaporizing coil adapted to be connected with a point of use.

3. In combination in a liquefied gas storage and dispensing system, a tank, and a take-off connection comprising conduit forming means in communication with the interior of said tank, a pressure reducing regulator positioned in communication with said conduit, a vaporizing coil lying within said tank in a position to be immersed in liquid therein, a connection from said regulator to said vaporizing coil and a second connection from said vaporizing coil extending to a \point of use.

4. In combination in a liquefied gas storage and dispensing system, a tank, and a take-off connection comprising conduit forming means in communication with the interior of said tank, a dip tube extending relatively close to the bottom of said tank and being in communication with said conduit forming means, a pressure reducing regulator positioned in communication with said conduit, a vaporizing coil lying within said tank in a position to be immersed in liquid therein, a connection from said regulator to said vaporizing coil and a connection from said vaporizing coil extending to a point of use.

5. In combination in a liquefied gas storage and dispensing system, a buried tank adapted to contain a liquefied fuel in heat exchange relation with the. earth, and a take-off connection comprising conduit forming means in communication with the interior of said tank, a pressure reducing regulator positioned in communication with said conduit, and a vaporizing coil lying within said tank in a position to be immersed in liquid therein, a connection from said regulator to said vaporizing coil and a second connection from said vaporizing coil extending to a point of use.

, 6. In combination in a liquefied gas storage and dispensing system, a buried tank adapted to contain a liquefied fuel in heat exchangerelation with theearth, and a take-oil connection comprising conduit forming means in communication with the interior of said tank; a dip tube terminating toward the bottom of said tank and being in com munication with said conduit forming means, a pressure reducing regulator positioned in communication with said conduit, a vaporizing coil lying within said tank in a position to be immersed in liquid therein, a connection from said regulator to said vaporizing coil and a second connection from said vaporizing coil extending to a point of use, a second regulator joined to said second connection.

7. An apparatus for supplying fuel of substantially uniform composition and at a low pressure from a mixture of liquefied petroleum gases; said apparatus comprising an under ground tank, conduit means extending from said tank to a place where the fuel is consumed, and means for regulating the flow of duel through said conduit means; said conduit means including a section having its inlet adjacent the bottom of said tank, a second section connected to the first section and having a coil portion submerged in a body of liquid in heat exchange relation with the earth and without mixture with the 'fuel passing through the conduit means, and a service conduit communicating with the second section; and said control means including a pressure reducer arranged between the first and second sections of said conduit means.

ROBIN BAKER. JAMES C. FLEMING.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

